Refrigeration system



July 259 1950 F. n. PELTIER 2,516-586 REFRIGERATION ss'ma Filed Nov. l., 1947 INVENToR. FRHDK D. PLT/R `Patented July 25, 1950 2,516,586 REFBIGERATION SYSTEM Frank D. Peltier,

Philco Corporation,

ration of Pennsylvania Application November 1, 1947,. Serial No. 783,487

ZCIaims.

This invention relates to refrigeration apparatus and, more particularly, to household refriginvention is especially concerned with evaporators of the type adapted to operate at temperatures below the freezing point of water. Evaporators of this type are frequently so located as to be contacted by moisture-laden air in the refrigerated compartment, and are thus susceptible to resultant rapid frost accretion or accumulation. The frost accumulated on the surfaces of the evaporator adversely affects the operation thereof and must be periodically removed if the effectiveness of the system is to be maintained at a desirable level. Such defrosting necessarily involves a substantial interruption in the refrigerating process and may result in spoilage of stored foodstuffs, particularly frozen foods.

It is a principal object of the present invention to provide novel and inexpensive evaporator means of such a nature as substantially to eliminate the necessity for such interruption of the refrigerating process in order to effect defrosting of the refrigerator.

The invention also has as a broad object the provision of an improved refrigerator especially adapted for household use.

Another and more detailed object of the invention resides in the provision of a novel evaporator of the above-stated type, so constructed that the eiective thermal transfer surfaces thereof, exposed to the. ambient air, are constituted by readily detachable elements of evaporator structure, said elements precluding direct contact between the evaporator and moistureladen air and further being readily removable from the structure in order to provide for removal of accumulated frost.

It is a feature of the invention that the aforesaid detachable elements may take the form of conventional ice trays, or other suitable receptacles.

The invention resides further in certain novel features of constructional arrangement hereinafter described and illustrated in the attached drawing, wherein:

Figure l is a fragmentary elevational view of a refrigerator including an evaporator incorporating the concepts of the present invention;

Figure 2 is an elevational view illustrating the evaporator configuration preferably employed, the evaporator being shown as detached from, the refrigerator and the View being taken as looking up within the refrigerator of Figure 1;

erating machines and evaporators therefor. The

movable elements which shield the Jenkintown, Pa., assignor to Philadelphia, Pa., a corpo- Figure 3 is a fragmentary elevational view, on an enlarged scale, illustrating the manner in which the evaporator tubing may be associated with the refrigerator cabinet structure, and showing the preferred mode of support for the reevaporator; and,

Figure 4 is a fragmentary sectional view, illustrating a modification contemplated by the present invention.

Now with more detailed reference to vthese iigures, the refrigerator cabinet, designated in its entirety at I0, comprises a food storage compartment II dened by cabinet wall structure which includes an inner tank or liner l2, and an outer shell I3. As appears at IIa (Figure 3) the space between the outer shell and inner liner is filled with insulating material. Breaker strip means of low conductivity, designated generally by the reference character I 4, surrounds the access opening of the front wall of the cabinet and provides a thermal break between the forward edges of said inner liner and outer shell. As will be understood, the refrigerator would include a door (not shown) mounted to seal against the forward face of the cabinet in the general plane of the breaker strip structure I4. Shelves I5, of any desirable type, are mounted within the compartment Il, and there is further included a combined shelf and drip receptacle I6 arranged in the upper portion of the cabinet and the purpose of which will be referred to hereinafter.

As thus far described, the construction is of known type, the compartment II being adapted for storage of foodstuffs and normally being maintained at temperatures well above the freezing point of Water. relative humidity of the air in such compartments frequently reaches rather high values.

In particular accordance with the present invention, there is disposed within the compartment II a refrigerant evaporator element I1, which, in a preferred embodiment of the present invention, takes the form of tubing IB (see particularly Figure 2) secured in convoluted arrangement closely adjacent to a wall of the inner liner l2. Preferably, although not necessarily, said tubing is disposed adjacent to the upper wall of the compartment, in order that elements of the structure presently to be described may serve also as receptacles for water to be frozen.

As will be best understood from consideration of Figures 2 and 3, the tubing I8, which comprises the evaporator I1, includes upper anging shown at I 9 and which is. in the illustrated form As will be recognized, the

3 oi' the invention, secured directly to the upper wall of inner liner I2; securement of the flanging I9 to the said upper wall 2li being accomplished by welding or the like. Vaporizable liquid refrigerant may be delivered to the tubing I8 in any convenient manner such, for example, as delivery through a capillary tube, a portion of which appears at 2|, and gaseous refrigerantmay be withdrawn from the evaporator through the suction line identified at 22. The tubing I8 is arranged in series circuit relation with a suitable condensing unit which, for the purposes of the present invention, may be of any known type. Since the construction and operation of such condensing units is well known in the art, and since the present invention is not concerned therel the result of condensation of moisture on the with, illustration and further description are not Y necessary herein.

As appears to best advantage in Figure 3, the

evaporator tubing I8 further includes lower support structure 23 comprising laterally extending ilanging secured along the lower surface of, the tubing. This lower Hanging cooperatesas between adjacent tubing convolutions-to provide confronting guideways, or slides 24, within which may be received outwardly turned flanges provided upon the elements or means utilized to shroud the lower surface of the evaporator tubing, and thus preclude contact between the tubing and the air in the compartment. Preferably, and as shown, this shroud means takes the form of ice trays, designated at 26, which trays are removably mounted within the guideways 24 through the agency of the aforesaid outwardly turned flanging 25.

It is of importance that the upper edges of the ice trays or elements 26 reside very closely adjacent to the lower surface of tubing I8 to eliminate, insofar as possible, circulation of air between the trays and the tubing. By virtue of this construction, the heat is abstracted from the storage compartment by thermal transfer between the air in the compartment and the evaporator tubing, which transfer takes place through the trays 26. During normal operating periods, excess moisture within the compartment II is deposited upon the lower surfaces of the elements or trays 26, and frost accumulation between the trays and the tubing is substantially eliminated. The invention contemplates the use of convenient means (not illustrated) for breaking any frost bond which might occur between the flanging 25 and the guideways 24, under conditions of extremely high humidity. Also, if desired a narrow band or cover member may encircle the tubing I8 in the plane of the convolutions, to prevent any frost accumulating upon tubing surfaces exposed in the narrow gap between the cabinet wall and the subjacent trays.

Tubing of the character contemplated by this invention may be readily manufactured, complete with the described guideways and securing anging, by an extruding process and, as shown in Figure 2, the guideway anging 23 is cut away as at 2l, along the forward edge of the cabinet. In this way open-ended parallel guideways are provided which terminate along the forward portion of the structure, and the ice trays or other elements 26 may be introduced into and removed from the forward portion of said guideways in the manner which will now be clearly understood from Figure 3. 1

As above mentioned, the shelf Ii lcomprises a shallow receptacle, such provision being desirable since some small amount of drip may occur as 75 ice trays,` between the time when the water in these trays reaches the dew point temperature of the air in the storage compartment, and before sub-freezing temperatures are attained.

If desired, and as illustrated in Figure 4, the construction may be modified in such manner as to space the tubing I8 from the adjacent wail of the liner I2, further to insure against the access of moisture-laden air to the region of said wall. As illustrated, this embodiment includes a baille or plate, shown fragmentarily at 28, which is spaced somewhat from the upper wall of the compartment, extends thereacross, and may be slidingly received within suitable mounting blocks 29, of low heat conducting material. Also, and as illustrated in both embodiments disclosed, cover members 30 may be secured to the guide- Way structure 23, in order substantially to eliminate the possibility of frost accumulation upon the lower surfaces of the guideway structure. Such cover members may be made of any suitable material of low thermal conductivity. It would, of course, be possible to provide upon the ice trays additional lateral extensions. spaced below the iianges 25, and substantially covering the guideway structure 23. However, it will be understood that the invention contemplates such changes and modifications as may come within the spirit of the subjoined claims.

As will now be understood, the present invention provides an improved refrigerator including non-frosting evaporator apparatus which is of a highly effective and inexpensive type. Contact of moisture-laden air with the evaporator surface is almost completely eliminated, and frost deposition within the box is localized upon the bottom and side walls of the removable ice trays, or other elements within the described guideways. The apparatus is further advantageous in that such localization of frost deposition is accomplished while still preventing undesirable accumulation of frost upon the frozen ice masses, per se. When the ice trays are removed from the evaporator, in order to obtain ice cubes therefrom, the frost accumulation may be very readily removed from said trays by immersing them momentarily in warm water.

I claim:

1. In a refrigerator, an inner liner defining a storage compartment, auxiliary wall means disposed closely adjacent a wall of the storage compartment, said auxiliary wall means being supported by said inner liner and maintained in thermally non-conductive relation therewith, a refrigerant evaporator carried by said auxiliary wall means, and a plurality of receptacles removably disposed closely adjacent said evaporator and cooperable with said wall means to preclude direct contact between the major portion of the surface of said evaporator and the air in said compartment.

2. In a refrigerator, a storage compartment, cooling means for said compartment including an evaporator mounted adjacent the top wall of the compartment and lower portions of which would normally be exposed within said compartment, said evaporator including metallic tubing and integral ilanging extending therefrom and forming channels depending from said tubing into a position in which surfaces of said Hanging would normally be exposed within the compartment, cover means comprising ice trays removably carried by said channels in close adjacency to said evaporator and arranged in high heat conducting relation with respect to said lower portions. said ice trays precludingr direct contact between tile of this patent:

UNITED STATES PATENTS Name Date Troiel May 17, 1927 Davenport July 1, 1930 Lenning June 12, 1934 Schweller Oct. 27, 1936 Chilton Feb. 2, 1937 Heitman Mar. 30, 1937 Allyne July 16, 1940 Caldwell. Dec. 3, 1940 Hall July 6, 1948 

